Rates of HCV Reinfection Are Low among People with Injection Drug Use Who Receive HCV Treatment
Although reinfection is cited as a reason not to offer HCV treatment to people with injection drug use (IDU), rates of reinfection after treatment are unclear. Researchers examined HCV reinfection* rates using data from a prospective cohort study** of individuals with recently acquired HCV. Those who did not achieve spontaneous virologic suppression were offered 24 weeks of HCV treatment. Of 163 participants enrolled, 76% reported IDU. Less than one-third (31%) were coinfected with HIV. Participants with treatment-induced virologic suppression were followed for a mean of 1.2 years (range, 0-2 years). Those with spontaneous virologic suppression were followed for a similar amount of time. Rates of HCV reinfection were calculated using Poisson distribution. Multivariable logistic regression was used to identify factors associated with reinfection.
- Of the 111 eligible participants who enrolled in treatment, 79% achieved virologic suppression by the end of treatment.
- Among successfully treated participants, 5 cases of reinfection occurred, which translated into an incidence of 4.7 cases per 100 person-years (95% confidence interval [CI]: 1.9, 11.2). Among untreated participants who had spontaneous suppression, the reinfection rate was 6.1 per 100 person-years (95% CI: 1.5, 24.6).
Factors independently associated with reinfection (n=13) were poor social functioning at enrollment and IDU during follow-up.
*Defined as the detection of an HCV strain distinct from the primary infecting strain among participants with either spontaneous or treatment-induced HCV virological suppression.
**The Australian Trial in Acute Hepatitis C (ATAHC).
Comments:
The rate of HCV reinfection after treatment in this study was slightly higher than that reported in prior studies, but still relatively low. Although the study is limited by short follow-up and infrequent sampling for HCV RNA, it is the largest study of reinfection to date. These results do not support withholding HCV treatment from people with IDU; however, education and support for substance abuse treatment to reduce the risks of reinfection should be included as part of treatment.
Judith Tsui, MD, MPH
Reference:
Grebely J, Pham ST, Matthews GV, et al. Hepatitis C virus reinfection and superinfection among treated and untreated participants with recent infection. Hepatology. 2012;55(4):1058–1069.